The Next Power Plant Is on the Roof and in the Basement
On any given Monday in Vermont, Josh Castonguay, the vice-president of innovation at that state’s Green Mountain Power utility, told me, he studies the forecast for the days ahead, asking questions like “What’s it looking like from a temperature standpoint, a potential-of-load standpoint? Is there an extremely hot, humid stretch of a few days coming? A really cold February night?” If there is trouble ahead, Castonguay prepares, among other things, Vermont’s single largest power plant, which isn’t exactly a power plant at all—or, at least, not as we normally think of one. It’s an online network, organized by the utility, of forty-five hundred electric storage batteries (currently, most of them are Tesla Powerwalls), spread out across more than three thousand Vermont homes. The network also...
